The original purpose of the Friday visit was for Duke to sign over the rights to his space memorabilia to the museum. Much of the memorabilia has been in the museum collection for years, but 2012 legislation switched ownership from NASA to the individual astronauts. Duke wanted to formalize his long-ago donation in his own name.

Museum officials took the chance to give Duke a quick tour of the new observatory, planetarium and 4D theater slated to open on Aug. 16. He was impressed.

"I've been working off-and-on on this project for about 20 years," Duke said. "Being South Carolina's first astronaut, I started to come over and started lobbying the Legislature and corporations and individuals. It was a struggle, but we finally got some traction after a few years, and now to see the fruition of all of that hard work that hundreds of people put into it ... is very satisfying."